The last functional civilian airport in Libya has halted operations, amid reports of airstrikes in the vicinity of the capital, as the Libyan National Army led by Marshall Khalifa Haftar continues its siege of Tripoli.

"The civilian aviation authority closed the air space of the airport until further notice for the sake of air security," Mitiga airport announced on its website, following reports of air strikes in Tripoli. The airport has not been hit.

Explosions and heavy fire were heard in the Libyan capital after an aircraft reportedly circled for several minutes over the city, Reuters said, citing witnesses on the ground. Meanwhile, the Arab media reported that an aerial bombardment had targeted a unity government-controlled site in Tripoli, but that no immediate details of casualties or damage was available.

Clashes in the southern districts of Tripoli raged throughout Saturday between militant groups loyal to Libya's internationally recognized Government of National Accord (GNA) and Marshal Haftar's LNA fighters, who launched their 'anti-terrorist operation' in Tripoli on April 3. The rival forces were each reported to be using airplanes to sway the outcome of the battle, which so far has claimed over 200 lives with hundreds more wounded.

"Our airforce is providing fire support to troops on the ground," Ahmed al-Mesmari, spokesman for Haftar's forces said - while GNA forces confirmed carrying out seven air raids against LNA positions on Saturday. Mesmari also accused GNA of siding with al-Qaeda and other terrorist networks to keep their control of Tripoli.

Libya has been devastated by a prolonged civil war, following NATO's intervention and months of airstrikes in 2011 that helped armed rebels hunt down and assassinate long-time ruler Colonel Muammar Gaddafi.